Polybutenyl-alkylene polyamine-polyalkanol lubricant additive and lubricating compositions containing same

ABSTRACT

IN WHICH R is a polybutenyl radical having a molecular weight from 900 to 10,000 and a mineral lubricating oil composition containing said polybutenyl-alkylene polyamine polyalkanol.   Polybutenyl-alkylene polyamine-polyalkanol ashless dispersant lubricant additive represented by the general formula:

United States Patent [191 Miller et al.

[4 1 May 20, 1975 1 1 POLYBUTENYL-ALKYLENE POLYAMINE-POLYALKANOL LUBRICANT ADDITIVE AND LUBRICATING COMPOSITIONS CONTAINING SAME [75] Inventors: Edward F. Miller, Wappingers Falls;

Walter W. Hellmuth, Hopwell Junction, both of NY.

[73] Assignee: Texaco Inc., New York, NY.

[22] Filed: Oct. 19, 1973 [21] Appl. No.: 408,226

Related U.S. Application Data [63] Continuation-impart of Ser. No. 155,286, June 21 1971, abandoned.

3,755,433 8/1973 Miller et al. 252/5l.5 R X 3,784,474 l/1974 Brown et a] 252/51.5 R 3,794,586 2/1974 Kimura et al. 252/5l.5 R

Primary Examiner-Delbert E. Gantz Assistant Examiner-Andrew H. Metz Attorney, Agent, or FirmT. H. Whaley; C. G. Ries; J. J. OLoughlin 571 ABSTRACT Polybutenyl-alkylerie polyamine-polyalkanol ashless dispersant lubricant additive represented by the general formula:

in which R is a polybutenyl radical having a molecular weight from 900 to 10,000 and a mineral lubricating oil composition containing said polybutenyl-alkylene polyamine polyalkanol.

7 Claims, No Drawings POLYBUTENYL-ALKYLENE POLYAMINE-POLYALKANOL LUBRICANT ADDITIVE AND LUBRICATING COMPOSITIONS CONTAINING SAME BACKGROUND OF THE INVENTION Straight mineral lubricating oils cannot meet the lubricating needs of modern internal combustion engines and it is customary to incorporate additives in the base oil giving a formulated lubricating composition having enhanced dispersant, detergent, corrosion inhibiting and antiwear properties. The problem of providing a satisfactory motor oil is compounded because these lubricants are subjected to a wide range of operating conditions. In particular, it is rather difficult to formulate a motor oil composition which will be effective under both continuous, high temperature, high speed operating conditions as well as under low-temperature stop and go driving conditions. This problem is further aggravated when the motor oil is intended for service in different type engines, i.e. diesel and gasoline engines, both of which put very severe but different stresses on the motor oil composition.

PRIOR ART Motor oil compositons for internal combusion engines containing polyolefin-substituted polyamines have been disclosed in US. Pat. No. 3,275,554.

A copending patent application, Ser. No. 208,978 filed Dec. 16, 1971 now US. Pat. No. 3,755,433 discloses a lubricating oil composition containing a polyisobutenyl-substituted N-aminoethylethanolamine as an ashless dispersant,

SUMMARY OF THE INVENTION An oil-soluble ashless dispersant for a mineral lubricating oil composition comprising a polybutenylalkylene polyamine-polyalkanol is provided as well as a mineral lubricating oil composition containing same. The polybutenyl-alkylene polyamine-polyalkanol is represented by the general formula:

in which R is a polybutenyl radical having a molecular weight from 900 to 10,000, X and Y represent H or (R"-O) 1-l at least one ofX or Y being (RO),,H, R is a divalent hydrocarbyl radical having from 2 to 8 carbon atoms. R is a divalent hydrocarbyl radical having from 2 to 4 carbon atoms, x has a value from 1 to 6 and y has a value from 1 to 5. Alternatively, the polyisobutenyl radical R will consist of from about 70 to 700 carbon atoms.

A formulated mineral lubricating oil composition will generally contain the dispersant in a concentration ranging from about 0.1 to 10 weight percent with the preferred concentration being from about 0.2 to 5 per- The polybutenyl-alkylene polyamine-polyalkanol dispersant compound of the invention is broadly represented by the general formula:

in which R is a polybutenyl radical having a molecular weight from 900 to 10,000, X and Y represent H or (RO),,H at least one of X or Y being (RO),,H. R is a divalent hydrocarbyl radical having from 2 to 4 carbon atoms, x has a value from 1 to 6 and v has a value from 1 to 5'. Y

A preferred class of compounds are those in which R is a polybutenyl radical having a molecular weight from 1000 to 5000, with a more preferred class being those in which R is a polybutenyl radical of 1200 to 2500 moleweight.

The symbols X and Y represent hydrogen or the radical (R"O) 1'l with at least one of Xv or Y. being (R O)yH. The dispersants of this invention thus can be represented by the formulas:

and

in which R has the values noted hereinabove.

The compound of the invention contains at least two hydrooxyalkyl radicals per mole of the compound attached to the same or different nitrogen atoms in the compounds. It willbe appreciated that a substantially larger number of hydrooxyalkyl groups can be present in the compounds hereinabove defined.

The prescribed polybutenyl-alkylene polyaminepolyalkanol can be prepared in two steps involving a reaction between a polybutenyl polymer and an alkylene polyamine in the first step to form an intermediate compound followed by a reaction with an alkylene oxide in the second step.

The polybutenyl component for the above reactions is a polymer of isobutylene which can be prepared by known polymerization methods. This polymer will have an average molecular weight ranging from 900 to 10,000. A preferred polubutenyl polymer is one having an average molecular weight ranging from 1000 to 5,000 with the most preferred having a molecular weight from 1200 to 2500.

The alkylene polyamine component employed can be a straight or branched chain diamine or a polyalkylene polyamine of mixture thereof. Examples of suitable diamines include ethylene diamine, propylene diamine, 1,4-butane diamine, 1,4-pentane diamine and 1,6- hexane diamine. Examples of suitable polyalkylene polyamines include diethylene triamine, piperazine, trieth yl ene tetramine, N-aminoethylpiperazine, tetraethylene pentamine and pentaethylene hexamine.

One method of reacting the polybutenyl polymer with the alkylene polyamine is to first prepare a halogen derivative, i.e. a chloride or bromide derivative of the polybutenyl polymer containing from 0.5 to percent of the halogen according to known methods as set forth in U.S. Pat. No. 3,275,554 which disclosure is incorporated herein. This halogenated polybutenyl polymer is then reacted with the prescribed alkylene polyamine. In general, 1 to 2 moles of the alkylene polyamine is reacted with the halogenated polybutenyl polymer. This reaction is preferable conducted in the presence of an alkaline material to facilitate the reaction. However, the reaction can be conducted without employing alkaline material and in the absence of a sol- CH CH OH The intermediate compound is then reacted with an alkylene oxide to form the dispersant of the invention. The preferred alkylene oxides for this reaction include ethylene oxide, propylene oxide and butylene oxide although higher alkylene oxides and alkyl substituted alkylene oxides are also suitable. This reaction is generally conducted by dissolving the intermediate compound in a hydrocarbon solvent and gradually adding the alkylene oxide reactant to the reaction mixture over a period of time. The reaction is conveniently conducted at room temperature although higher and lower temperatures generally ranging from about 0 to C. can be employed. The ratio of alkylene oxide to alkylated alkylene polyamine is at least 2:1 and is generally in the range of 2:1 to 10:1 with the preferred range being 2: l to 5:1. These ranges effect alkoxylation of the primary and secondary nitrogen atoms as well as for polyalkoxylation at these points. The reaction mixture is then filtered and the solvent stripped off under a vacuum.

The following table lists the dispersants which are prepared according to this invention:

N-hydrox- N-polybutene (C N N bis-2 hydroxyethyl diethylenetriamine e R-N- cH N-polyisobutenyl (C CH CH CH 2 2 N-CHH CH -N (CH CH OH) -N,N ,N"-tetrakis-2 hydroxy-ethyl diethylenetriamine.

R-N-CH N-polyisobutenyl C 0 N" bis-2 hydroxyethyldiethylenetriamine N-polyisobutenyl (Cam-N"bis-2-hydroxyethyldiethylenetriamine CH '-CH 2 N-polyisobutenyl (C m-N,N"-bis-2-hydroxypropyldiethylenetriamine dissolved in 800 milliliters of toluene and 334 milliliters of isopropyl alcohol. 232 grams (4 moles) of propylene oxide was added dropwise to the solution of the intermediate product over a min. period. The mixture CH -CH OH H H H R-N CH CH NCH CH N--CH -CH -NCH CH OH N-po1yisobutenyl(C )-N,N'-bis-2-hydroxyethy1- was then heated to reflux for 4 hours, filtered and the triethylenetetramine I solvents stripped off under vacuum at 200F. The dis- C!H CH -OH CH CH OH CH -CH OII (CH CH OH) 2 R-N CH -CH -N CH -CH -NCH -CH N N-polyisobutenyl(C )-N,N',N",N"'-pentakis-2- hydroxyethyl-triethylene tetramine.

The hydrocarbon mineral base oil employed in preparing the lubricating oil compositions of the invention can be a paraffinic base, naphthene base of mixed paraffin-naphthene base distillate or residual oil. Paraffin base distillate lubricating oil fractions are preferred for the formulation of the highest quality engine or motor oils. The lubricating oil base generally will have been subjected to solvent refining to improve its lubricity and viscosity temperature relationship as well as to solvent dewaxing to remove waxy components and to improve the pour of the oil. Generally, mineral lubricating oils having an SUS viscosity at 100F between '50 and 1000 may be used in the formulation of the improved lubricants of this invention with the preferred oils having a viscosity range from 70 to 300 SUS at 100F. A blend of base oils can be employed to provide a suitable base oil foreither a single or multigrade motor oil.

The following example illustrates a method for preparing the ashless dispersants of the invention.

EXAMPLE I 4,620 grams of chlorinated polybutene having a mo- 0 lecular weight of about 1300 and containing 2.76 percent of chlorine was mixedwith 500 grams (4.3 moles) of hexamethylene diamine and 191 grams (1.8 moles) of sodium carbonate. The reaction mixture was cooled, diluted with four liters of hexane, filtered and the filtrate extracted with methanol. The hexane'layer was stripped under vacuum at 200F. yeilding an intermediate product containing 0.8 percent nitrogen.

2,340 grams of the above intermediate product was persant product contained 0.8 percent nitrogen.

The effectiveness of the dispersant of the invention was determined in the Caterpillar l-H Diesel Engine Test. This is a standard industrytest which is run on a 1Y73 single cylinder Caterpillar Diesel Lubricant Test Engine as described in FTMS 791a-346T. This test is used to qualify lubricants for MIL-L2104B.

The engine is operated at a speed of 1800 RPM and a fuel input of 4950 BTU/min for a test duration of 480 hours. Performance is judged by examination of the power section of the engine for ring sticking, piston deposits and ring, piston and liner wear.

EXAMPLE [I EXAMPLE [11 Following the procedure of Example I, 3500 g of a chlorinated polybutene containing 2.76% chlorine, 632 g (2.7 mole) of pentaethylenehexamine, and g 1.3

mole) of sodium carbonate is reacted to give a product containing 2% nitrogen.

Reaction of 1500 g of the above intermediate in 1000 ml toluene and 350 ml isopropyl alcohol with 200 g (3.4 ml) of propylene oxide, gave a dispersant material containing 2% nitrogen.

CATERPILLAR l-H TEST The lubricating oil composition employed in this example was fully formulated motor oil composition containing an alkaline detergent, a zinc dithiophosphate and a pour depressant in a paraffinic mineral oil having an SUS viscosity at 100F. of 535. The detergent of Example was added to the fully formulated base oil in an amount to give 0.028% nitrogen in the finished oil.

The foregoing oil composition was tested in the Caterpillar 1-H Test for the full test duration of 480 hours. Inspection of the piston showed 5% TGF, and 100% light lacquer on the first land and no deposits below. These results demonstrate the effectiveness of the dispersant for controlling both carbonaceous and lacquer deposits in diesel engine operation.

The detergent of the invention was also treated for its effectiveness in motor oil compositions for a gasoline engine. The formulated oils were evaluated in laboratory bench tests (Bench Sludge I and Bench Sludge 11 tests) designed to discriminate between oils of differing light duty deposits control characteristics. The bench Sludge tests are a measure of the ability of a dispersant formulation to retain particulate foreign materials. The numbers obtained indicate the depth of sediment (in millimeters) obtained at the end of the test procedure. In general, the lower the values in the Bench Sludge I and 11 tests are, the more highly dispersant the formulations are.

The base oil employed was a paraffmic hydrocarbon oil having an SUS at 100F of about 125. Three fully formulated oils were prepared containing an alkaline detergent, zinc dithiophosphate and a polymethacrylate pour depressant in addition to the dispersants described above. Lubricating oil A contained the dispersant of Example I to give a fully formulated oil containing 0.028 percent nitrogen. Lubricating oil B contained the dispersant of Example 11 to give a fully formulated oil containing 0.036 percent nitrogen. Lubricating oil C contained the dispersant of Example III to give a fully formulated oil containing 0.081% nitrogen. Lubricating oil D contained no ashless dispersant.

The results of the Bench Sludge Tests are given in Table I below.

TABLE I BENCH SLUDGE TESTS Bench Sludge I (mm Sediment) Bench Sludge ll (mm Sediment) l. Lubricating Oil A 0.1 0.5 2. Lubricating Oil B 0.3 0.7 3. Lubricating Oil C 0.] 0.4 4. Lubricating Oil D 0.5 3.8

(no dispersant) effective for controlling deposits in four cycle gasoline engine type operation which this test simulates.

We claim:

1. A lubricating oil composition comprising a major amount of a mineral lubricating oil and a dispersant amount of an oil-soluble ashless polybutenyl-alkylene polyamine-alkanol having the structural formula:

in which R is a polybutenyl radical having a molecular weight from 900 to 10,000, X and Y are H or (R"O- )yH at least one of X or Y being (R -O)y-H, R is a divalent hydrocarbyl radical having from 2 to 8 carbon atoms, R" is a divalent hydrocarbyl radical having from 2 to 4 carbon atoms, x has a value from 1 to 6 and y has a value from I to 5.

2. A lubricating oil composition according to claim 1 in which the polybutenyl radical in said dispersant has a molecular weight ranging from 1000 to 5000.

3. A lubricating oil composition according to claim 1 in which the polybutenyl radical in said dispersant has a molecular weight ranging from 1200 to 2500.

4. A lubricating oil compsoition according to claim 1 in which said dispersant is represented by the formula:

in which the symbols have the values given in claim 1.

5. A lubricating oil composition according to claim 1 in which said dispersant is represented by the formula:

in which the symbols have the values given in claim 1.

6. A lubricating oil composition according to claim 1 in which said dispersant is represented by the formula:

CH CH OH H 2 2 I (CH2 CH2 N) (CH2 CH2 o) H in which R, x and y have the values given in claim 1.

7. A lubricating oil composition according to claim 1 in which said dispersant is represented by the formula:

in which R. .r and y have the values given in claim I.

l= l= l l =1 

1. A LUBRICATING OIL COMPOSITION COMPRISING A MAJOR AMOUNT OF A MINERAL LUBRICATING OIL AND A DISPERSANT AMOUNT OF AN OIL-SOLUBLE ASHLESS POLYBUTENYL-ALKYLENE POLYAMINE-ALKANOL HAVING THE STRUCTURAL FORMULA:
 2. A lubricating oil composition according to claim 1 in which the polybutenyl radical in said dispersant has a molecular weight ranging from 1000 to
 5000. 3. A lubricating oil composition according to claim 1 in which the polybutenyl radical in said dispersant has a molecular weight ranging from 1200 to
 2500. 4. A lubricating oil compsoition according to claim 1 in which said dispersant is represented by the formula:
 5. A lubricating oil composition according to claim 1 in which said dispersant is represented by the formula:
 6. A lubricating oil composition according to claim 1 in which said dispersant is represented by the formula:
 7. A lubricating oil composition according to claim 1 in which said dispersant is represented by the formula: 